技術標籤：java比較器

//先建立一個實體類
package course.comparable2;

public class Dog implements Comparable<Dog> {
      private String name;
      private int age;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int
 
 getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public Dog(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public Dog() {
    }

    @Override
    public String toString() {
        return "Dog{"
 
 +
                "name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
//內部比較器
    @Override
    public int compareTo(Dog o) {
        return Integer.compare(this.getAge(),o.getAge());
    }
}

//建立外部比較器
package course.comparable2;

import java.util.
 
Comparator;

public class MyComparable implements Comparator<Dog> {



    @Override
    public int compare(Dog o1, Dog o2) {
        return o1.getName().compareTo(o2.getName());
    }


}

package course.comparable2;

import java.util.Arrays;

public class Test {
    public static void main(String[] args) {
        Dog [] dogs = {
                new  Dog("來福",1),
                new  Dog("二哈",3),
                new  Dog("大黃",4),
                new  Dog("小白",2)
        };
        //內部比較器的使用
        System.out.println(dogs[0].compareTo(dogs[1]));
        //外部比較器的使用
        Arrays.sort(dogs, new MyComparable());
        //Arrays.sort();
        System.out.println(Arrays.toString(dogs));
    }
}